Other notes

This is not a "plug and play" server implementation. In order to implement OAuth
correctly as a provider you have more work to do: token storage, nonce and timestamp
verification etc.

This is not a "bells and whistles" HTTP client. If you need fine grained control
over your HTTP requests or you prefer to use something other than inets/httpc then you
will need to assemble the requests yourself. Use oauth:sign/6 to generate a list of
signed OAuth parameters, oauth:uri_params_encode/1 or oauth:header_params_encode/1 to
encode the parameters, and then assemble the request using your HTTP client of choice.